A study of synthesis, characterization and metalloplex formation ability of cetylpyridinium chloride based metallosomes

Abstract Controlled stoichiometry in organic–inorganic hybrid surfactants (metallosurfactants) leads to the formation of liposomal structures (metallosomes). This versatile approach provides a new strategy for preparing metallosomes with transition metal salts from single tail cationic surfactant as a precursor. Four different types of metallosomes having same organic counterpart but different transition metals (Fe, Co, Ni and Cu) were synthesized from metallosurfactants. The spherical morphology of synthesized metallosomes was confirmed with transmission electron microscopy (TEM), atomic force microscopy (AFM) and small angle X-ray scattering (SAXS) studies. The multivesicular nature of metallosomes was supported by TEM results. From DLS studies, hydrodynamic size and polydispersity index was found to vary with counter metal-ion. Presence of lamellarity within metallosomal structure was supported with XRD. More detailed information on lamellarity of the metallosomal structure was obtained with SAXS experiments. As metallosomal structures are able to mimic biological membranes; hence, their binding behavior towards calf thymus DNA (CT-DNA) was investigated. Appreciable binding efficiency of metallosomes towards DNA was affirmed with fluorescence spectroscopy and ζ-potential studies. Conformational changes were observed from gel retardation assay, providing vivid proof of DNA-metallosomes interactions.